Sanding machine



June 25, 1963 E. MUAQSCHEI. 3,094,819

SANDING MACHINE Filed'Aug. 6, 1962 5 Sheets-Sheet 1 22 22 Jnvenar':

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June 25, 1963 E. MuRscHEL 3,094,819

sANnING MACHINE Filed Aug. e, 1962 s sheets-sheet a 1`4 54 64 4s 5o ya52 5 92 afz as 102100 69 9o 10a 88105 4 o zo s" WW2/21mm@ /I-H-orneysUnited States Patent O 3,094,819 SANDING MACHINE Erwin Murschel,Stuttgart-Weilimdorf, Germany, assignor to C. F. Scheer & Cie.,Stuttgart-Feuerbach, Germany Filed Aug. 6, 1962, Ser. No. 215,156 Claimspriority, application Germany Aug. 10, 1961 17 Claims. (Cl. 51-170) Thisinvention relates in general to sanding machine construction and inparticular to a new and useful hand belt sander having improved meansfor adjusting the tensioning and the run of the belt automatically.

The present invention is an improvement over previous -belt sandingmachine constructions, particularly in respect to the means for mountingthe tensioning roller to permit easy adjustment thereof at a locationwithin the roller. Such means permit adjustment both in outward andinward tensioning directions and in directions along lthe roller axis.The inventive construction also provides improved means for insuringguidance of the belt from the `driving roller over the tensioningroller.

With prior art machines of this type it is essential that there is alarge 4free space between rollers for the adjusting devices. This, forexample, applies to machines which are driven by flexible shafts. In ahand belt sander, however, it is desirable that a driving motor beplaced between the driving and tensioning rollers and hence there is nospace for any adjustment means.

In accordance with the present invention there is provided ian improvedbelt san-der construction which includes the housing frame :havinghandle means thereon which supports a central motor and a drivingrollerat one end thereof :and a tensioning 'roller adjustably mounted atthe other end thereof. The tensioning roller is advantageously supportedfrom the housing on an adjustable pin assembly which includes means forbiasing the tensioning roller in a direction outwardly to tension anendless sanding belt directed thereover whenever the pin assembly isarnanged in this manner. The outward tensioning may be easily removedfrom the tensioning roller Iby means of a control pin which is arrangedto shift a rocking lever supporting the bearings of the tensioningroller so that a biasing spring no longer acts thereon to force theroller in an outward direction tensioning the sanding belt.

YThis inventive construction includes a rocking lever constructionsupporting the shaft of the tensioning roller which permits both theoutward and inward movement of the roller for the purpose of tensioningthe belt and also permitting the axial adjustment of the shaft for thepurposes of displacing the tensioning roller laterally in thoseinstances where it is desinable to -adjust the run of the belt, such asfor diagonal sanding, for example.

The inventive device permits easy changing of the belt by depressing acontrol pin to remove the tension acting on a roller through a torsionspring arranged in the pin assembly. The rocking lever carrying thetension roller shaft may then be swung easily backwardly with the rollerbearings and the tension roller to permit easy re moval of the sandingbelt. The improved construction includes means `for adjusting thetransverse position of Ithe tensioning roller and for biasing the rollerbearing shaft in a predetermined direction during the operation thereof.F[he arrangement permits easy running of the tensioning roller andaslight shifting axially thereof in the even-t of an unbalancing offorces or overload.

A `fur-ther feat-ure of the invention includes means `for mountingadjustable guide elements on each side of the tensioning roller whichinclude arm portions which extend upwardly and then circum-ferentiallyaround the lateral periphery of the belt for insuring the true ru-nningof the tensioning roller and preventing the :lateral displaceice men-tof the belt from the roller. In the event of a onesided load acting onthe sanding belt, the belt will run up against one of the guide elementsand prevent it from being completely displaced out of alignment. Inaddition, the running-up pressure is transmitted through the guideelements to the tensioning roller axis which is thereafter rocked ordisplaced laterally causing the belt to move to the highest plane whichis formed by the displacement of the tensioning roller. The guideelements are advantageously constructed as a quarter of -the circleguide rod which overlies the circumference of the tensioning rolleradjacent each edge;

A feature of the invention is that the lateral displacement of the axisof the tensioning roller is permitted by a novel mounting means whichincludes a rockable bearing formed as a partial ball or ball dishconstruction. The ball or ball-shaped bearing is advantageously heldwithin a socket formed in a bore in the rocking lever and means areprovided to urge the ball bearin-g which carries the tensioning shaft ina predetermined direction to one side. The construction advantageouslyincludes means 'for shifting the rocking lever in an axial or transversedirection for the purpose of shifting the tensioning roller for thoseinstances in which it is desirable t-o run the belt at an angle. A setscrew element is provided to set the rocking lever in lthe adjustedposition. The adjustment is advantageously made by shifting a slidingpin element of the pin assembly which carries the rocking lever at theinner end thereof.

Accordingly, it is an object of this invention to provide an improvedhand sander construction.

A further object of the invention is to provide a hand sander whichincludes a housing supporting a central motor and rotatably supporting adriving roller at one end, and including rocker means pivotallysupporting the shaft yfor the tensioning roller, the rocker means beingadjustable for tensioning purposes and including means for biasing therocker means to an loutward tensioning position.

A further object of the invention is to provide a hand sanderconstruction including an improved mounting for a tensioning rollerwhich comprises an improved pin assembly supported in the sander housingand carrying a rocking lever at the inner end thereof with means biasingthe rocking lever in an outward position to tension a sanding belttrained around the tensioning roller and -inlcluding a control pinarrangement which may be displaced to effect removal of the action ofthe biasing means on the roller for the purpose of slackening thesanding belt, such as for removal purposes.

A further object of the invention is to provide an im.- proved handsander construction which includes adjustable means for supporting theshaft of a tensioning roller to permit axial as well as outward orlongitudinal displacement thereof for adjustment purposes.

A further object of .the invention is to provide ka hand sanderincluding an improved support for a tensioning roller which includes arocking lever having a bore therein with a ball socket portion adaptedto receive a ball bearing portion of the tensioning roller shaft, meansbeing provided to bias the shaft in a lateral direction against the balisocket portion against the rocking lever, said rocking lever beingdisplaceable laterally to permit lateral shifting of the location ofsaid tensioning roller.

A further object of the invention is to provide the sanding device whichincludes means supporting a shaft of a tensioning roller for axialdisplacement and guide ele- 3 off the side of the tensioning roller, thesupporting spindle being mounted so that it will be rocked when theguide elements are contacted by .the belt and displaced thereby.

A further object of the invention is to provide a hand sanderconstruction which is simple in design, rugged in construction andeconomical to manufacture.

The various features of novelty which characterize the invention arepointed out with particularity in the claims annexed to and forming apart of .this specification. For a better understanding of 4theinvention, its yoperating advantages and specific objects attained byits use, reference should be had to the accompanying drawings andVdescriptive matter in which there are illustrated and describedpreferred embodiments of the invention.

In the drawings:

FIG. l is a perspective right-hand elevation of a sander constructed inlaccordance with the invention;

FIG. 2 is a section taken on the line 2 2 of FIG. l on an enlargedscale;

FIG. 3 is a section taken on the line 3-3, of FIG. l on the same scaleas FIG. 2 with the exception itis also extending 4through the tensioningroller axis;

FIG. 4 i-s a partial horizontal top plan of the portion of the sanderindicated in FIG. 3;

FIG. 5 is a ri-ght-hand end elevation of the tensioning roller on aslightly larger Iscale than FIG. 2;

FIG. 6 is a section taken on the line 6 6 of FIG. 3 indicating theroller in a non-tensioned position;

FIG. 7 is a section similar to FIG. 6 but indicating the roller in atensioned position;

FIG. 8 is a fragmentary section of another embodiment of rocker levermounting for the tensioning roller shaft;

FIG. 9 is a longitudinal section of still another embodiment of rockerarm mounting for the tensioning roller shaft;

FIG. 9a is a top View of FIG. 9; and

FIG. 10 is an enlarged fragmentary side elevation of the control pin andabutment stop.

Referring to the drawings in particular, the invention embodied thereinincludes a hand vbelt sander indicated in position on a wooden board orplate 10. The sander includes a machine casing 14 provided with a handle12 at one end thereof. An electrical outlet cord 13 is provided forconnecting a driving motor 16V to an electrical power source. The motor16 is centrally mountedwithin the interior of the casing 14 and includesmeans (not shown) for driving a drive roller 18 mounted at one endthereof. The tensioning roller 20 is rotatably mounted onY the oppositeend and an endless sanding belt 22 is directed over each of the rollers18 and 20. A guide shoe 24 is provided at the lower side of the motor 16over which the belt 4runs and the shoe insures the proper positioning ofthe machine on the workpiece to. be worked upon. In order to suck offany Wood dust which is -accumulated during the sanding, there isprovided at the machine casing a suction .device Z6 having a dustreceiving bag 28.

In accordance 'with the invention there is provided an improved mountingfor the tensioning roller 20 to insure lthe automatic tensioningcompensation or equalization as well as the automatic ladjustment of therun of the sanding belt. The adjustable mounting means includes, as bestindicated in FIGS. 2 and 3, -a carrier pin assembly generally-designated 32 arranged at a securing Wall 30 of casing 14. By means 'ofa suitable mounting or bearing (not shown) both the drive motor 16 andthe drive roller 18 are secured at the wall 30. The pin assembly 32includes an elongated hollow pin piece or member 34 which is slidable ina `bore or groove 37 dened in the wall 30. T he pin 34 is prevented fromrotating by means of an extension 3S of a set screw member 40 whichrides in an axially elongated groove 36 of the pin member 34. The setscrew 40 is threaded in a top portion of a projection of the wall 30 andextends into the groove 36. The set screw 40 may be adjusted manually inorder to permit the axial sliding of the pin 34, and notches -or detents42 are advantageously `cut out along the groove in order to providespaced anchoring recesses at which the pin 34 may be anchored lby theset screw 40. A rocker arm or lever arm member 46 is rotatably mountedadjacent the inner end of the pin 34. The rocker arm member 46 includesan outer lend with a bore 86 defining an internal socket ledge portionat the inner end thereof for the purposes of receiving a ball shapedbearing mounting 84 for a bolt shaft yor spindle 89 for the tensioningroller ZG.

A torsion spring 50 is twirled around the pin 34 and one of its ends is-held in an adjusting ring 52 and its opposite end bears against thelever member 46 by pressing against a securing ring 54 which extendsaround the pin 34. The spring exerts a biasing force on the rockinglever member 46 to urge it in an outwardly direction away from the driveroller 1S. This maintains the :roller 20 under an outward biasing totension the sanding belt 22 which is trained to run therearound.

As indicated in FIG. 4, the right-hand end of the spring 50, designated56, bears against an abutment pin 5S which is inserted into the ring 52While the left-hand end designated 60 bears against a holding piece 62of the rocker arm member 46 to urge it outwardly with `a relativelystrong spring force. Due to the action of the torsion spring 50 thetensioning roller is rocked outwardly in accordance with the indicationshown in FIG. 7 in a counter-clockwise manner. This insures that thebelt 22 Will be maintained in tension during the operation of thedevice.

In -accordance with the invention, in order to exchange the belt 22 ofthe machine in a rapid and easy manner, there is provided a control pin64, as indicated in FIG. 3, which extends through the -hollow pin 34.The pin 64 is slidable in the hollow pin 34. The end of the pin 34 isprovided with a forked extension 66 which is angled olf and defines aguideway perpendicular to the axis of the pin. The pin 64 extendsthrough the guideway and is biased in position thereon by spring 72.Rotation of the control pin is impossible When it is located between theforked elements 66. The spring 72 is coiled around the control pin 70and -abuts against an inner widened portion of the bore of the pin 34 onone end and a control knob 70 on the outer end of the pin 64. At theinner end of the rocker arm 46 there is provided an abutment pin 68 withan inclined or slanted surface 69, las indicated in FIG. 10. When thecontrol pin 64 is moved inwardly in the direction of arrow D, the end issnapped over the abutment 68, as indicated in FIG. 6, .so that thetensioning roller may be moved by hand to the untensioned position linwhich the abutment 68 prevents the torsion spring from tensioning theroller. After the |belt is positioned in place, the tensioning may beresumed 4by merely displacing the control pin 64 in the direction of thearrow D once 4again to the extent that the pin will be released fromthe. abutment 68 Iand the rocker will be retens-ioned by the spring 50.

As mentioned previously, the outer end of the rocker member 46 isprovided with a bore 86 for the purpose of mounting the roller axis,which is generally designated by the numeral 82. The ball-shaped' recessis formed at the inner end of the bore 86 and provides a ball socket for=a partial ball joint dish member or bearing 88 to permit slightrotational adjustment, of :an axle or supporting spindle 89, which iscarried in the ball joint piece 88. By this arrangement the run of thebelt is automatically controlled, so that the belt will always be llushwith the inside of the two rollers. The arrangement permits the rockingmovement of the spindle or bolt shaft 89 which rotatably carries thetensioning roller 20. For this purpose the tensioning roller 20 includesra central web wall 20a which carries an elongated barrel portion inwhich is mounted ball be-a-rings 90. Ball bearings 90 are advantageouslyaxially spaced to provide a secure supporting arrangement for thetensioning roller on t-he bolt member 89.

In accordance with a feature of the invention, one end of the tensioningroller is held in its position by an adjusting ring 92 which is ttedover the bolt shaft 89 and secured thereto such as by a set screw (notshown). As indicated in FIG. 5, a stirrup member or guide rod 94 extendsradially outwardly from the adjusting ring 92 and includes an arcuate orbent portion which extends circumferentially along the side of thetensioning roller and in closely spaced position in respect thereto,`such as indicated in FIG. 2. As indicated in FIG. 3, the outer surfaceof the guide rod 92 extends by ran amount a beyond the circumference ofthe tensioning roller. This -position can be yadjusted by means of theset screw 96 which is arranged in the Iadjusting ring 92 (FIG. 5).

An additional'stirrup member or guide rod 98 is arranged in an extensionportion 102 of the bolt shaft 89 :at the opposite end and extendsradially and then arcuate- 1y around a portion of the circumference ofthe tensioning roller in the manner of the guide rod 9'4. A set screw100 secures the rod in `an adjusted position at the selected he-ightabove the tensioning roller. Each of the guide rods 94 and 98 providesmeans for insuring the proper feeding of the sanding belt 22 over thetensioning roller `and any tendency for the belt to slide off either endthereof will cause a rocking movement of the bolt shaft 89 and anadjustment of the tensioning roller, so that the belt will tend Vto bedisplaced toward a high portion of the roller andan :auto-maticcompensation will `be made.

As indicated in FIGS. 3 and 4 the lball joint piece 84 is provided witha through bore in which is inserted an adjusting pin 105 which is guidedin a slot like recess 108 Vformed in the outer end of the lever member46. Lateral projections of the upper end of the lever member 46 arefor-med as outwardly extending spindle guide arms 110 :and 62. In thespindle lguide arm 110, as indicated in FIG. 4, there is arranged `athreaded spindle 112 which may be threaded into the guide 110 againstthe force of a compression spring 114 to cause an outer end thereof tobear -against the adjusting pin 105. The spring 115 heldin the guidespindle 62 bears against the opposite end of the pin 105 so that theball piece 84 always bears in t-he socket 86 under a predeterminedbiasing force. This permits adjustment of the bolt shaft 89 by rockingmovements against the biasing force to accommodate for any unbalancingforces for -acting on the sanding belt. "Iihe arrangement also permitsthe guide rod members 94 Iand 98 to rock the bolt shaft 89 when the beltbecomes misaligned on the tensioning roller. If it is desired it is alsopossible to release the Set screw 40 and shift the position of the pin34 so that the tensioning roller 20 may be positioned on the oppositeside of the housing and the belt run at an angle -so that the sandingm-ay be made in an excellent and clean manner on angular surfaces.

' In FIG. 8 another embodiment of a rocker bearing mount is indicatedwhich includes a rocking lever member 122 rotatably mounted on a pin120. As in the previous embodiment the rocker is held in a tensionedposition by a torsion spring (not shown). A holding pin 124 permits thetensioning of the lever member 122 by being positioned against one sideof an abutment 126 and also permits the untensioning by the shiftingbeyond the abutment as indicated in the previous embodiment. In thisembodiment a cylindrical recess 130 is provided at the outer end of therocker arm member 122. The other end of the rocking lever member 122 isprovided with a bore 130 for mounting `a bearing bolt 128 which carriesthe tensioning roller (not shown). A partially ball-shaped joint piece132 is positioned over the bolt shaft 128 and is positioned so that itcontacts the walls of the bore 130. At a distance from the point piece132 the bearing bolt 128 is provided with an abutment member 134 for thepurpose of providing a rigid point which bears against the right-handend face of the rocker according to FIG. 8.

This also insures that in spite of this engagement the bearing bolt 128can be rocked in each direction. The end portion of the rocker member122 is provided with a surface 136 which is partially 'ball-shaped. Atthis surface the abutment member includes a curved or ball-shaped innerportion 138 which bears over the projection 136. The bearing bolt isguided by means of -a pin 140 which is arranged in the rocking levermember 122 in an elongated slot 142. By means of `an adjusting spindle(not shown, but comparable to the other embodiments), the pin is biasedso that the bolt -shaft 128 is urged to the left, as indicated in thedrawings.

In FIGS. 9 and 9u another embodiment of means for mounting the bearingbolt -for the tensioning roller is shown. A rocker 152 is rotatable on abearing pin 150 and it carries a pivotal pin member 156 which issupported in a bore of the rocker member 152 by a projection 158. Theouter end of the pin member is provided with a fork 154 which carries ahorizontal pin 171 at its outer ends. The bolt shaft or axis 162 for thetensioning roller is arranged in a bearing piece which is pivotallysupported by the pin 171. The rocker 152 is fitted with two arms 15211and 152b. In a threaded hole of the former a threaded spindle 172 isthreadedly engaged which bears with its forward end 172a against theright hand end 'a (-see FIGS. 9 and 9a) of pin 171, which is heldagainst said forward end 172a by means of a biased compression spring170, said spring being with one end located in a hole of arm 152b andbears with its other end against the left hand end 171b (see FIGS. 9 and9a) of pin 171.

By turning the threaded spindle 172 it is thus possible to change thecross-wise position of pin 171 and thus of the shaft 162 carrying Ithetensioning roller.

Thus the invention provides an inexpensive sanding device with improvedmeans for .adjusting the tensioning roller in a variety of ways. Thetensioning roller may be shifted axially and rocked about its axis aswell as displaced outwardly for tensioning purposes. Alignment of thebelt is always assured by means of the guide rods which correct for anyunbalancing forces by shifting the axis of the tensioning roller. Whilespecific embodiments of the invention have been shown and described indetail to illustrate the application of the inventive principles, itwill be understood that the invention may be embodied otherwise withoutdeparting from such principles.

I claim: l

'1. A belt sander comprising a casing, a driving motor supportedcentrally in said casing, a driving Iroller arranged at one end of saidmotor to be rotatably supported in said housing at one end of said motorand connected to -said motor for rotation thereby, a tensioning rolleradjacent the opposite end of said motor, a rocking lever memberpivotally mounted on said casing and Vhaving a free end extendingcentrally of said tensioning roller, a tensioning roller shaft, bearingmeans rotatably supporting said tensioning roller on said shaft, saidrocking lever member having rocking bearing means -adjustably supportingsaid tensioning roller shaft within the tensioning roller for rockingadjustable movement, the rocking lever member being pivotal on saidhousing to permit movement of said tensioning roller outwardly fortensioning purposes.

2. A belt sander according to claim l, including means to bias saidrocking lever member outwardly in a tensioning position.

3. A belt sander according to claim 2, including a tensioning relievingabutment defined on an end of said rocking lever member, a control pinheld against rotation in respect to said rocking lever member and beingaxially displaceable out of the path of said abutment, said tensioningroller with said rocking lever member being displaceable by handinwardly against said biasing force to permit positioning of saidcontrol means on the opposite side of said abutment, said abutmentpreventing said rocking lever member and said tensioning roller frombeing biased outwardly beyond a predetermined position.

4. A belt sander according to claim 1, wherein said means adjustablysupporting -said bolt shaft includes a bore defined in said rockinglever member with an internal ball socket ledge portion, and a balljoint piece carried around said 4bolt shaft positioned in said bore androtatably displaceable on said ball socket ledge portion, and means tobias said bolt shaft in a direction urging said ball joint piece intoengagement with the ball ledge portion of said lever member bore.

5. A belt sander according to claim 4, wherein said means urging .saidbolt shaft in-to engagement with the ball-shaped ledge portion of Saidlever member bore includes first and second arms projecting on each sideof said lever member, a bolt member extending through said ball jointpiece on each side thereof in alignment with the arms of said levermember, spring means extending from one of said arms against said boltpiece and an adjustable pin member bearing against the opposite of saidarms.

6. A belt sander according to claim 1, including a pin slidably mountedin said housing, said lever member being rotatably carried on said pin.

7. A belt sander comprising a housing, a driving motor secured to saidhousing, a driving 4roller connected to said motor for rotation thereby,a tensioning roller, a rocking lever member, axially movable meansrotatably supporting said rocking lever member within said tensioningroller, a tensioning roller bolt shaft, said tensioning roller beingrotatable on said bolt shaft, and means defined adjacent the free end ofsaid rocking lever member rockingly supporting said bolt shaft.

8. A belt sander according to claim 7, wherein said means defined onsaid rocking lever member includes a bore having a ledge portion formedas a curved socket portion, a ball socket piece within said bore havingcurved portions in sliding engagement with the socket portion of saidrocking lever member bore, s-aid ball socket piece being connected tosaid bolt shaft.

9. A belt sander according to claim 8, including a pin extending throughsaid ball socket piece, said bol-t shaft having an elongated slotthrough which said pin extends.

110. A belt sander according to claim 9, including means for biasingsaid pin, in a direction urging said ball socket piece into engagementwith the curved portion of said rocking lever member bore.

11. A belt sander according to claim 7, wherein said means rotatablysupporting said rocking lever member within said tension roller includesa pin slidably mounted in said housing, and set screw means for xingsaid pin in a slidably adjusted position in said housing.

12. A lrocking lever member according to claim 7, including va guide rodmember affixed to at least one end of said bolt shaft, including 4aportion extending in a curve around a portion of the circumference ofsaid tension roller forming a guide for an endless sanding beltpositioned over said driving roller and said tension roller.

13. A belt sander comprising a housing including a side bearing supportwall portion, a driving motor secured to said housing, a driving rollerconnected lto said motor for rotation thereby, a tensioning roller, apin slidably but non-rotatably mounted in said housing, a rocking levermember rotatable on said pin, spring means urging said rocking levermember lto rotate in a direction away from said driving roller, atension roller bolt shaft, said tension roller being rotatable on saidbolt shaft, and means defined adjacent the free end of s-aid rockinglever member and on said bolt shaft rockingly supporting said bolt shafton said lever member.

14. A belt sander according to claim 13, including a control pinslidable in said pin and having ya portion bent at the inner end thereofat right angles to said pin, guide means on the exterior of said pin atan angle to the axis thereof, the control pin being held by said guidemeans against rotation relative to said pin but being displaceable outof said guide means, an abutment defined on said control lever memberand preventing said spring means from moving said rocking lever memberlfully outwardly when said control pin is positioned on one sidethereof, said control pin being displaceable out of said guide means topermit positioning thereof on the opposite side of said abutment `and topermit said spring means to urge said rocking lever with said tensioningroller fully outwardly in a belt tensioning position.

l5. A belt sander according to claim 13, including a guide rod connected-to said bolt shaft adjacent at least one end thereof, and including acurved portion extending around a portion -of the circumference of saidtension roller, said guide rod being adjustable to permit the outercurved end thereof to be located at a preselected height outwardly fromthe periphery of said tension roller.

16. A belt sander according to claim 13, wherein said means definedonsaid bolt shaft and said lever member includes ball and socket jointmeans supporting said shaft in said lever member. j 17. A belt sanderaccording to claim 16, including a pin extending through said ball andsocket joint means, and means biasing said pin in a direction towardengagement of the ball and socket joint means.

References Cited in the file of this patent UNITED STATES PATENTS

7. A BELT SANDER COMPRISING A HOUSING, A DRIVING MOTOR SECURED TO SAIDHOUSING, A DRIVING ROLLER CONNECTED TO SAID MOTOR FOR ROTATION THEREBY,A TENSIONING ROLLER, A ROCKING LEVER MEMBER, AXIALLY MOVABLE MEANSROTATABLY SUPPORTING SAID ROCKING LEVER MEMBER WITHIN SAID TENSIONINGROLLER, A TENSIONING ROLLER BOLT SHAFT, SAID TENSIONING ROLLER BEINGROTATABLE ON SAID BOLT SHAFT, AND MEANS DEFINED ADJACENT THE FREE END OFSAID ROCKING LEVER MEMBER ROCKINGLY SUPPORTING SAID BOLT SHAFT.